Focus on Fungicides

Focus on Fungicides

Being a serious wheat grower means focusing closely on fungicides

All of the highest yielding wheat fields in Ontario will be protected by a combination of two fungicides.  Your wheat crop did not slow down much in the face of this cool and wet weather.  Your choice will depend how thick your crop is, and how susceptible your variety is to the strains in your region.  All of the early planted wheat stands are showing some degree of powdery mildew, and septoria.  Tan spot found also.  Leaf rust is heavy in concentrated areas.  Stripe Rust is being found by the hour.  Keep up the good scouting!!   Talk to your supplier reps to ensure that the right product is chosen to target proper disease.  Be sure to use a combination of products with multiple modes of action as good resistance management.  And, use LOTS of water for max coverage.

A hypothetical Q&A from grower questions received recently…

Grower:  “Wet field conditions did not allow me to spray the herbicide or apply a T1 fungicide.  Weeds don’t seem to be threat.  Looks like T3 won’t be far away, why don’t I just wait?”

The Wheat Team:  Assuming your field is well developed and has a thick canopy, you will want adjust your sights on a T1.5>T2 timing.  All of the fungicides work in a preventative fashion, and they need to be applied proactively, and before disease sets in.  If your flag leaf is emerged, protect that upper canopy.  The Flag Leaf is the main method to capture sunlight and keep that plant factory operating at full capacity.  This early fungicide will also keep the stems clean and assist for greater standability (want to avoid lodging in thick stands.).

Grower:  “Can I tank mix my fungicide with second pass of fertilizer?”

The Wheat Team:  Unfortunately NOT.  Timing might match up, the application methods do not.  Fungicides need to be applied with a fat fan nozzle and high water volumes, the goal is to paint it on the leaves.  Liquid Fertilizer needs to be applied with coarse streamer nozzles and the goal is to get the liquid to the ground for plant uptake through roots.  For best results, and least visual damage, separate these applications by at least three days.

Grower:  “When it dries up, which comes first… do I apply T2 fungicide or second app fertilizer?”

The Wheat Team:  Allow the crop colour to tell you.  If the crop has healthy colour and does not appear to be missing nutrients, apply the fungicide first.  If the crop is showing pale colour from lack of nutrients, apply the fertilizer as soon as conditions allow, then following with fungicide.

About the Author

Tim Meulensteen is a CCA-ON certified Agronomist with C&M Seeds. He farms with his family in Perth County. Tim attended the University of Guelph and graduated with a Bachelors of Commerce in Agriculture. He has been working in the Ontario agriculture industry since 2004.